type lietype = E6 | E7 | E8 | F4 | G2

(* From string to lietype *)
val of_string : string -> lietype

(* Rank of a Lie algebra given its type *)
val rank : lietype -> int

(* The poset matrix of the extended root poset given a Lie type *)
val matrix_ext_root_poset : lietype -> bool array array
